We are developing two high-throughput technologies for materials modification. The first is a repetitive intense ion beam source for materials modification through rapid surface melt and resolidification (up to 1010 K s−1 cooling rates) and for ablative deposition of coatings. The short range of the ions (typically 0.1 to 10 μm) allows vaporization or melting at moderate beam energy density (typically 1–50 J cm−2). A new repetitive intense ion beam accelerator called CHAMP is under development at Los Alamos. The design beam parameters are: E = 200–250 keV, I = 15 kA, τ = 1 μs, and 1 Hz. This accelerator will enable applications such as film deposition, alloying and mixing, cleaning and polishing, corrosion and wear resistance, polymer surface treatments, and nanophase powder synthesis. The second technology is plasma source ion implantation (PSII) using plasmas generated from both gas phase (using radio frequency excitation) and solid phase (using a cathodic arc) sources. We have used PSII to directly implant ions for surface modification and as a method for generating graded interfaces to enhance the adhesion of surface coatings. Surfaces with areas of up to 16 m2 and weighing more than a thousand kilograms have been treated in the Los Alamos PSII chamber. In addition, PSII in combination with cathodic source deposition has been used to form highly adherent, thick Er2O3 coatings on steel for reactive metal containment in casting. These coatings resist delamination under extreme mechanical and thermal stress.

We describe the design of an intense, pulsed, repetitive, neutral beam based on magnetically insulated diode technology for injection into ITER for spectroscopic measurements of thermalizing alpha particle and thermal helium density profiles, ion temperature, plasma rotation, and low Z impurity concentrations throughout the confinement region. The beam is being developed to enhance low signal-to-noise ratios expected with conventional steady-state ion beams because of severe beam attenuation and intense bremsstrahlung emission. A 5 GW (e.g., 100 keV, 50 kA) 1 μs duration beam would increase the charge exchange recombination signal by 103 compared to a conventional 5 MW beam.

Summary form only given. A number of intense ion beam applications are emerging requiring repetitive high-average-power beams. These applications include ablative deposition of thin films, rapid melt and resolidification for surface property enhancement, advanced diagnostic neutral beams for the next generation of Tokamaks, and intense pulsed-neutron sources. We are developing a 250 keV, 15 kA, 1/spl mu/s duration, 1-30 Hz intense-ion beam accelerator called CHAMP (continuous high average-power microsecond pulser). The accelerator will use a magnetically insulated extraction diode in ballistically focused geometry.

This paper presents the electrical system design methodology which the authors are developing for use in the Los Alamos “CHAMP” (continuous high-average power microsecond pulser) program. CHAMP is a magnetically confined anode plasma diode (MAP diode) intense ion source. The CHAMP diode ion source requires many synchronous modulator sub-systems slaved to that required by the diode discharge itself (200 kV, 20 kA). In addition to overall CHAMP diode system requirements, the design of the pertinent electrical pulse modulator systems is also presented